Bastexwireless via Amazon offers preorders of the Bastex The Dress Heavy Duty iPhone Case 2-Pack for iPhone 6 or iPhone 6 Plus for $16.99. Coupon code "THEDRESS" cuts it to $9.99. With free shipping, that's $7 off and the lowest total price we could find. It includes a black/blue case and a gold/white case.
Note: The iPhone 6 model will be released on March 27.